Trolley-head for electric traction.



PATENTED OCT, 29. 1907.

ALLEN.

G. B. HOLMES & A. D. TROLLEY HEAD FOR ELECTRIC TRACTION.

APPLICATION FILED AUG.7. 1907.

I conditions.

GARNET BOWEN HOLMES AND ARTHUR DUNSUOMBE ALLEN,

ZEALAND.

PATENT OFFICE.

O F WELLINGTON, NEW

TROLLEY-HEAD FOR ELECTRIC TRACTION.

Specification of Letters Patent.

Patented Oct. 29, 1907.

I Application filed'August 7. 1907- Serial No. 387.485-

To all whom it may concern: Beit known that we, GARNET B WEN Homrns and ARTHUR DUNSCOMBE ALLEN, subjects of His Majesty the King of Great Britain and Ireland, both residing at -Wellington, New Zealand, have invented new and useful Improvements in TrolleyHeads for Electric Traction, of which the following isa specification.

Our invention relates to improvements in trolley heads, and it consists in the constructions, combinations and arrangements herein described and claimed. The object oi our invention is to provide an improved trolley head of simple and durable construction, which will automatically accommodate itself to all irregularities and curvatures of the trolley wire for maintaining an eilicient contact with the latter under all practical In the accompanying drawings, forming a part of this application and in which'similar reference numerals indicate corresponding parts in the several views Figure 1 is a side elevation, illustrating one embodirnent of our invention; Fig. 2 is a plan view, partly broken away, of the construction shown in Fig. 21;

' .and Fig. 3 is a perspective view of a preferred form of blocks and yoke jaws, respectively, for normally maintaining said bearing blocks in the upper. portions of the inclined slots 5. The springs 10 thus constitute yield-' ing buffers for maintaining the trolley wheel in contact with the trolley wire, and preventing shocks due to irregularities in the latter.

- A spindle 16 is suitably secured in.the bearing blocks, as by' split pins 17, and rotatably supports a trolley wheel 2. Springs 13 are interposed between said trolley wheel and bearings for yieldingiy positioning the .wheel on its spindle; said springs being shown secured to the bearings by rivets 14.

.The curved faces 18 enable the bearing blocks and spindle 16 to swing as a whole in the yoke to permit automatic swing of the trolley wheel for adjustment of the latter to curvatures of the trolley wire; Such ad- Patent is i justing swing of the trolley wheel will compress one or the other of the springs 10; said springs constituting yielding means for auimnaiically returning the trolley wheel to its n'i'irnial straight position. The rounded studs 1 l and 12, extending within the respective ends of the springs 10, enable said springs to accommodate themselves to the swing of the bearing blocks and spindle, and insure efficient action of the springs 10 in all positions of said bearing blocks.

In previous constructions, it has been usual to provide the trolley wheel with a contact groove of considerably greater width than that necessary to receive the trolley wire, in order to prevent the trolley wheel slipping from position when traveling along curved portions of said wire, In these previous constructions, it has been found that the bottom of such widened groove in the trolley wheel is irregularly worn by the trolley wire to produce ridges in the bottom of said groove: thereby car sing abnormal sparking and an 1 ineflicient contact between the trolley wheel and wire. By our invention, it is practical to provide the trolley wheel with a V-shaped groove having 7 the bottom fornied of such width that it will be subjected to uniform wear throughout by contact with the trolley wire.

We have illustrated and described preferred and satisfactory constructions; but. obviously, changes could be made within the scope of our invention.

Having thus described our invention, what we claim as new therein and desire to secure by Letters 1. In a trolley head, the combination of a yoke provided with slots, bearing blocks slidablymounted in said slots, :i-spindie secured to said bearing blocks, a trolley wheel carried by said spindle, curved flanges on said blocks engaging the walls of said yoke to permit swing of the blocks and spindle; springs for automatically returningsaid blocks and spindle to their normal straight position, and means on the yoke and blocks for engaging said springs to permit; accommodation of the latter to the swing of said blocks, substantially as described.

2, in a trolleyhead, the combination of a yoke providcd with inclined slots, bearing blocks slidabiy mounted in said slots, ospindle secured to said hearing blocks, a trolley wheel carried by said spindle. curved flanges on said blocks engaging the walls of said yoke to permit swing of the blocks and spindle, and springsfor shifting suid bearing blocks against the upper ends of said inclined slots and yieldingiy maintaining said. blocks and spindle in their normal straight position in the scverni shiftedv positions of the latter, substsntiailyms described.

3. In a trolley head, the combination of a yoke provided with slots, bearing blocks siidnbly mounted in said slots, :1 spindle secured to said bearing blocks, a trolley wheel carried by-said spindle, curved flanges on said ting passage of its spindle therethrough, substantially as blocks engaging the walls of said yoke to permit swing described. of the blocks and spindle, springs for automatically re- In testimony whereof we have signed our names to this tuining said blocks and spindle to their norm-Lil straight specification in the presence of two witnesses. 5 position, means on the yoke and blocks for engaging said springs to permit accommodation of the latter to the E BOWEN HOLMES swing of said blocks, and fiat springs secured to said bear ARlHUR DULYSCOMBE ALLEN ing blocks and engaging the adjacent sides of the trolley Witnesses:

wheel for yieidingly positioning the latter on its spindle, ERNEST SMITH BALDWIN,

10 said flat springs beingprovided with openings for permit- I. I. WATSON. 

